The construction of an offshore wind farm requires the use of many different vessels working together. Sheringham Shoal has seen a fleet of different sized and shaped vessels carry out the different aspects of the offshore construction.
Starting with relatively small marine mammal and ornithological survey boats in 2004, the site has since seen an array of vessels including:
|Nordnes:||Using a precision technique the bulk carrier Nordnes placed rocks around the site of 79 of the 90 foundation locations to reduce the likelihood of scour and therefore protect the cables when they are installed.
Length: 164m Load capacity: 24,000 tonnes Width: 26m Loaded speed: 12 knots
|The Aura and Toisa Sonata originally brought the monopile foundations and transition pieces to the site from Vlissingen in the Netherlands. The "Aura” carried two foundations each voyage while the “Toisa Sonata” carried only the one.
Aura: Length: 95m Width 13m
Toisa Sonata: Length: 87m Width: 19m
Operated by contractor Visser and Smit, the Team Oman is a dynamic positioning vessel with a 3,400 tonne lift capacity with the responsibility for laying both the export and infield cables at Sheringham Shoal.
The 100m high self-powered heavy-duty floating crane Svanen, started the foundation installation work in 2010 but in 2011 was replaced by Oleg Strashnov, a state-of-the-art crane vessel designed for heavy lifting operations.
The Oleg Strashnov, operated by Seaway Heavy Lifting, placed both 1000 tonne substations on top of their foundations and completed the installation of the 90 turbines
Length: 183m Width: 47m Crew: 150
The GMS Endeavour is a self-propelled jack-up barge built in 2010, and operated by Gulf Marine Services. The Endeavour can accommodate around 60 people on board, and specialises in turbine transportation and installation, carrying two turbines to the site at a time.
Four legs each: 94.2m
In mid-2011 she was joined by the 91m SEA JACK, a self-elevating platform vessel and then in early 2012, SEA JACK was replaced by state-of-the-art, self-propelled 76m jack-up vessel Seajacks Leviathan, owned by Great Yarmouth-based firm Seajacks and operated out of the local port.
Replacing previous “floatel” the 153m Wind Ambition, which was required elsewhere, a recent addition to the Sheringham Shoal fleet is the 145m Regina Baltica, a former cruise ferry.
Toisa Warrior is responsible for burying all the infield cables between the turbines and the offshore substations, and the export cable between the wind farm and shore. The remotely operated trencher CT-1 which is equipped with the latest in technology including surveillance cameras, an echosounder and sonar will be housed onboard.
|Jan Steen and HAM 602||
The 78m Jan Steen's role is to complete the next phase of scour protection, carrying on from the laying of an initial filter layer of rock by the Nordnes in early 2010 (see above).
The third and final stage of the scour protection work will be carried out by the 83m HAM 602. A side stone placement vessel, the HAM 602 will put the final armour layer of larger rocks around the base of the foundations. She can accommodate up to 20 people, has a capacity of 2435 tonnes and can place armour layers of rocks around two foundation bases each day.